Adhesive, adhesive member, interconnecting substrate for semiconductor mounting having adhesive member, and semiconductor device containing the same

ABSTRACT

An adhesive which comprises (1) 100 parts by weight of an epoxy resin and a hardener therefor, (2) 75 to 300 parts by weight of an epoxidized acrylic copolymer having a glycidyl (meth)acrylate unit content of 0.5 to 6 wt. %, a glass transition temperature of −10° C. or higher and a weight average molecular weight of 100,000 or more and (3) 0.1 to 20 parts by weight of a latent curing accelerator; an adhesive member having a layer of the adhesive; an interconnecting substrate for semiconductor mounting having the adhesive member; and a semiconductor device containing the same.

TECHNICAL FIELD

[0001] The present invention relates to an adhesive, an adhesive member,an interconnecting substrate for semiconductor mounting having theadhesive member, and a semiconductor device comprising a semiconductorchip and an interconnecting substrate bonded together by using theadhesive member.

BACKGROUND ART

[0002] With the progress of electronic and electric equipment in recentyears, the mounting density of electronic parts has been increased, andnew packaging methods have becoming to be used, such as so-called chipscale packages or chip size packages (hereinafter, they will be referredto as CSP) with sizes nearly equal to semiconductor chips, and bare chippackaging.

[0003] Reliability is one of the most important characteristicsrequisite for packaging substrates mounted with various electronicparts, such as semiconductor elements. Particularly, connectionreliability against thermal fatigue is very important because itdirectly affects the equipment containing the packaging substrates.

[0004] One of the causes for the lowering of connection reliability isthe thermal stress due to the use of various materials having differentcoefficients of thermal expansion. That is, semiconductor chips havecoefficients of thermal expansion of as small as about 4 ppm/° C. whilewiring boards for mounting electronic parts have coefficients of thermalexpansion of as large as 15 ppm/° C. or more, so that thermal shockresults in thermal strain, which results in a thermal stress.

[0005] In conventional substrates mounted with semiconductor packagescontaining lead frames, such as QFP or SOP, the deformation of leadframes absorbs the thermal stress to keep reliability.

[0006] In bare chip packaging wherein the electrodes of semiconductorchips and the wiring pads of wiring boards are connected by solder ballsor by a conductive paste through small projections referred to as bumps,thermal stress concentrates to the connecting regions, to lowerconnecting reliability. Putting a resin referred to as “under fill”between chips and wiring boards is known to effectively disperse thethermal stress, but increases packaging steps and cost. Another methodis connecting the electrodes of semiconductor chips and the wiring padsof wiring boards by conventional wire bonding, which, however, alsoincreases the packaging steps because wires should be protected bycoating a sealing resin.

[0007] Because CSP can be mounted together with other electronic parts,various structures have been proposed as disclosed in Surface MountingTechnique, 1997-3, “The future of CSP (fine pitch BGA) being put intopractical use”, p 5, Table 1, published by Nikkan Kogyo Shinbunsha.Among them, those containing a tape or carrier substrate as aninterconnecting substrate called “interposer” have been increasingly putinto practical use. In the above-described table, the structuresdeveloped by Tecera Co., Ltd. and TI Co., Ltd. correspond to theabove-described structures. Because they contain an interconnectingsubstrate as an interposer, they excel in connection reliability aspublished in Shingaku Giho CPM96-121, ICD96-160 (1996-12), “Developmentof Tape/BGA-type CSP” and Sharp Giho, No. 66 (1996-12), “Chip SizePackage Development”.

[0008] Between the semiconductor chip and the interconnecting substratecalled interposer contained in such a CSP is used an adhesive memberthat decreases the thermal stress resulting from their difference incoefficient of thermal expansion. The adhesive member requires moistureresistance and high temperature endurance, and there is a demand forfilm-form adhesive members, which facilitate the production processcontrol.

[0009] Adhesives of the film type have been used in flexible printedwiring boards, and most of them contain acrylonitrile butadiene rubberas a main component.

[0010] Among those for printed wiring boards that are improved inmoisture resistance include an adhesive disclosed in Japanese PatentApplication Unexamined Publication No. 60-243180 (1985) which containsan acrylic resin, an epoxy resin a polyisocyanate and an inorganicfiller, and an adhesive disclosed in Japanese Patent ApplicationUnexamined Publication No. 61-138680 (1986) which contains an acrylicresin, an epoxy resin, a compound having urethane bonds in molecules andterminated by a primary amine at each end and an inorganic filler.

[0011] The adhesive members as described above should release thermalstress and be heat and moisture resistant. In view of productionprocesses, they also should neither allow an adhesive to flow out toelectrode areas provided on semiconductor chips for electric signaloutput nor leave vacant spaces between them and circuits formed oninterconnecting substrates. Flowing out of an adhesive to electrodeareas causes connection defects of electrodes, and vacant spaces betweena circuit and an adhesive tend to deteriorate heat resistance andmoisture resistance. It is therefore important to control the flowingamount of adhesives. Further, film-form adhesives containingthermosetting resins are subject to change with passage of time, therebydecreasing the flowing amount and bonding strength. Adhesive members,therefore, require control of the flowing amount and bonding strengththroughout their usable periods.

[0012] Film-form adhesives containing thermosetting resins graduallycure during storage. The adhesives further cure during various processesfor producing a package, including mounting a semiconductor chip on aninterconnecting substrate called interposer, fabrication of a package,etc. It is preferable to use an adhesive having a longer usable periodto improve the processability of the adhesive and the connectionreliability of semiconductor chips. That is, the longer the usableperiod is, the less the flowing amount and bonding strength decrease dueto the change with passage of time, facilitating the control of theflowing amount and bonding strength.

[0013] The usable periods of conventional film-form adhesives could beincreased by decreasing the content of the curing accelerator in anadhesive composition, but the curing rate was problematically lowered oncuring the adhesives to cause foaming. There has been a demand foradhesives, which do not foam but have longer usable periods and as wellsatisfy the requirement for low elasticity, heat resistance and moistureresistance.

[0014] Further, adhesives for use in semiconductor packages or wiringgenerally contain thermosetting high molecular weight components such asepoxy resins to improve heat resistance. The thermosetting highmolecular weight components, however, have the defects of requiring ahigh temperature and a long time for curing. To solve the defect, curingaccelerators have been used together with the thermosetting resins.Blending a curing accelerator greatly improves the curability, but hascaused another problem that the reaction proceeds even at roomtemperature, thereby changing the flowability of the adhesive duringstorage at room temperature to make the adhesive commercially useless.To solve the new problem, it was proposed to use a latent curingaccelerator having no activity at room temperature. For example,Japanese Patent Application Unexamined Publication No. 9-302313 (1997)discloses the use of a very latent imidazole as a curing accelerator forepoxy resins in adhesive compositions. The latent curing acceleratorimproves storage stability. However, it has been found that because theproduction process of adhesive films includes a heat treatment step forcuring the adhesive composition to B-stage and the partially reactedlatent curing accelerator becomes active even at room temperature, thereaction gradually proceeds to deteriorate storage stability. This hascaused a demand for further improvement of storage stability.

DISCLOSURE OF INVENTION

[0015] An object of the invention is to provide an adhesive and anadhesive member, which have a usable period of 3 months or more at 25°C. without deteriorating the low elasticity, heat resistance andmoisture resistance necessary for mounting a semiconductor chip onto aninterconnecting substrate, referred to as interposer, such as aglass-epoxy substrate or a flexible substrate, which are a largelydifferent in coefficient of thermal expansion. Other objects of theinvention is to provide an interconnecting substrate for semiconductormounting having the adhesive member and to provide a semiconductordevice wherein a semiconductor chip and an interconnecting substrate arebonded together by using the adhesive member.

[0016] Further, during the production of adhesive films, curingaccelerators partially undergo reaction in the step of heat treatment athigh temperatures in a coating drying furnace, so that the curingaccelerators exhibit activity due to decomposition, etc., even duringstorage at room temperature, not excepting latent curing accelerators.It has been found that the crosslinking polymer component in the filmsis crosslinked due to its particularly high activity, thereby changingflowability largely and deteriorating storage stability. In view of thisproblem, another object of the invention is to provide an adhesive to beused for producing adhesive films particularly excelling in storagestability.

[0017] Accordingly, the present invention relates to the followings.

[0018] 1) An adhesive (hereinafter, it may be referred to as adhesiveA), comprising (1) 100 parts by weight of an epoxy resin and a hardenertherefor, (2) 75 to 300 parts by weight of an epoxidized acryliccopolymer having a glycidyl (meth)acrylate unit content of 0.5 to 6 wt.%, a glass transition temperature Tg of −10° C. or higher and a weightaverage molecular weight of 100,000 or more and (3) 0.1 to 20 parts byweight of a latent curing accelerator.

[0019] 2) An adhesive, comprising (1) 100 parts by weight of an epoxyresin and a hardener therefor, (2) 5 to 40 parts by weight of a highmolecular weight resin being compatible with the epoxy resin and havinga weight average molecular weight of 30,000 or more, (3) 75 to 300 partsby weight of an epoxidized acrylic copolymer having a glycidyl(meth)acrylate unit content of 0.5 to 6 wt. %, a glass transitiontemperature Tg of −10° C. or higher and a weight average molecularweight of 100,000 or more and (4) 0.1 to 20 parts by weight of a latentcuring accelerator.

[0020] 3) The adhesive of 1) or 2), wherein the latent curingaccelerator is an adduct curing accelerator.

[0021] 4) The adhesive of 3), wherein the latent curing accelerator isan amine adduct.

[0022] 5) The adhesive of 4), wherein the latent curing accelerator isan amine-epoxy adduct.

[0023] 6) The adhesive of any one of 1) to 5), which contains 1 to 20parts by volume of an inorganic filler relative to 100 parts by volumeof a resin content of the adhesive.

[0024] 7) The adhesive of 6), wherein the inorganic filler is alumina,silica, aluminum hydroxide or antimony oxide.

[0025] 8) The adhesive of any one of 1) to 7), which has generated 10 to40% of heat to be generated by complete curing thereof as measured byDSC.

[0026] 9) The adhesive of any one of 1) to 8), which has a residualsolvent content of 5 wt. % or less.

[0027] 10) The adhesive of any one of 1) to 9), which gives a curedproduct thereof having a storage modulus of 20 to 2,000 MPa at 25° C.and having a storage modulus of 3 to 50 MPa at 260° C. as measured byusing a dynamic viscoelasticity measuring apparatus.

[0028] 11) An adhesive (hereinafter, it may be referred to as adhesiveB), which is an adhesive composition comprising two kinds of resinswhich when the composition is in a B-stage state, separate from eachother into a disperse phase and a continuous phase, a hardener and acuring accelerator, wherein in the B-stage state, the curing acceleratoris compatible with the disperse phase and separates from the continuousphase.

[0029] 12) The adhesive of 11), wherein in the B-stage state, thedisperse phase contains an epoxy resin and the curing agent as maincomponents, and the continuous phase contains as a main component a highmolecular weight component having a weight average molecular weight of100,000 or more.

[0030] 13) The adhesive of 12), wherein the high molecular weightcomponent having a weight average molecular weight of 100,000 or more isan epoxidized acrylic copolymer having a glycidyl methacrylate unitcontent or a glycidyl acrylate unit content of 2 to 6 wt. %.

[0031] 14) The adhesive of any one of 11) to 13), wherein the curingaccelerator is an amine-epoxy adduct.

[0032] 15) An adhesive member of a film form, comprising a carrier filmand a layer of the adhesive of any one of 1) to 14) formed on thecarrier film.

[0033] 16) An adhesive member, comprising a core material and a layer ofthe adhesive of any one of 1) to 14) formed on each side of the corematerial.

[0034] 17) The adhesive member of 16), wherein the core member is a heatresistant thermoplastic film.

[0035] 18) The adhesive member of 17), wherein the heat resistantthermoplastic film has a softening temperature of 260° C. or higher.

[0036] 19) The adhesive member of 17) or 18), wherein the core materialor the heat resistant thermoplastic film is a porous film.

[0037] 20) The adhesive member of any one of 17) to 19), wherein theheat resistant thermoplastic film is a liquid crystalline polymer.

[0038] 21) The adhesive member of any one of 17) to 20), wherein theheat resistant thermoplastic film is a polyamideimide, a polyimide, apolyetherimide or a polyether sulfone.

[0039] 22) The adhesive member of any one of 17) to 20), wherein theheat resistant thermoplastic film is a polytetrafluoroethylene, anethylene-tetrafluoroethylene copolymer, atetrafluoroethylene-hexafluoropropylene copolymer or atetrafluoroethylene-perfluoroalkyl vinyl ether copolymer.

[0040] 23) An interconnecting substrate for semiconductor mounting,comprising

[0041] an interconnecting substrate having a semiconductor chip mountingsurface and

[0042] the adhesive member of any one of 15) to 22) stuck on thesemiconductor chip-mounting surface of the interconnecting substrate.

[0043] 24) A semiconductor device, comprising a semiconductor chip andan interconnecting substrate bonded together by using the adhesivemember of any one of 15) to 22).

[0044] 25) A semiconductor device, comprising an interconnectingsubstrate and a semiconductor chip having an area of 70% or more of anarea of the interconnecting substrate, the interconnecting substrate andthe semiconductor chip being bonded together by using the adhesivemember of any one of 15) to 22).

BRIEF DESCRIPTION OF DRAWINGS

[0045]FIG. 1(a) is a sectional view of a film-form adhesive member of anembodiment according to the present invention, which consists of asingle layer of an adhesive, and FIG. 1(b) is a sectional view of anadhesive member of an embodiment according to the present invention,which comprises a core material and an adhesive layer provided on eachside of the core material.

[0046]FIG. 2(a) is a sectional view of an interconnecting substrate forsemiconductor mounting, which has a film-form adhesive member of thepresent invention comprising a single layer of an adhesive, and FIG.2(b) is a sectional view of an interconnecting substrate forsemiconductor mounting, which has an adhesive member of the presentinvention comprising a core material and an adhesive layer provided oneach side of the core material.

[0047]FIG. 3(a) is a sectional view of a semiconductor device wherein asemiconductor chip and an interconnecting substrate are bonded togetherby using a film-form adhesive member of the present invention comprisinga single layer of an adhesive, and the pads on the semiconductor chipare connected to the interconnecting line on the substrate by bondingwires; FIG. 3(b) is a sectional view of a semiconductor device wherein asemiconductor chip and an interconnecting substrate are bonded togetherby using an adhesive member of the present invention comprising a corematerial and an adhesive layer provided on each side of the corematerial, and the pads on the semiconductor chip are connected to theinterconnecting line on the substrate by bonding wires; FIG. 3(c) is asectional view of a semiconductor device wherein a semiconductor chipand an interconnecting substrate are bonded together by using afilm-form adhesive member of the present invention comprising a singlelayer of an adhesive, and the pads on the semiconductor chip are bondedto the inner leads of the substrate; and FIG. 3(d) is a sectional viewof a semiconductor device wherein a semiconductor chip and aninterconnecting substrate are bonded by using an adhesive member of thepresent invention comprising a core material and an adhesive layerprovided on each side of the core material, and the pads on thesemiconductor chip are bonded to the inner leads of the substrate.

EXPLANATION OF LETTERS

[0048]1. adhesive, 2. core material (heat resistant thermoplastic film),3. interconnecting line, 4. interconnecting substrate, 5. semiconductorchip, 6. bonding wire, 6′. inner lead, 7. sealing material, 8. lead forexternal connection

BEST MODE FOR CARRYING OUT THE INVENTION

[0049] The epoxy resin contained in the adhesive A of the presentinvention may be any one which has bonding effect after curing and isdifunctional or more, and preferably has a molecular weight or a weightaverage molecular weight of less than 5,000, for example not less than300 and less than 5,000, more preferably less than 3,000. Examples ofdifunctional epoxy resins include bisphenol A epoxy resins and bisphenolF epoxy resins. Bisphenol A epoxy resins and Bisphenol F epoxy resinsare marketed by Yuka Shell Epoxy Co., Ltd. under the trade names ofEPKOTE 807, EPIKOTE 827 and EPIKOTE 828, by Dow Chemical Japan Co., Ltd.under the trade names of D.E.R. 330, D.E.R. 331 and D.E.R. 361, and byTohto Kasei Co., Ltd. under the trade names of YD 8125 and YDF 8170.

[0050] To increase Tg, a polyfunctional epoxy resin may be added, suchas a phenol novolac epoxy resin or a cresol novolac epoxy resin. Phenolnovolac epoxy resins are marketed by Nippon Kayaku Co., Ltd. under thetrade name of EPPN-201. Cresol novolac epoxy resins are marketed bySumitomo Chemical Co., Ltd. under the trade names of ESCN-190 andESCN-195, by Nippon Kayaku Co., Ltd. as mentioned above under the tradenames of EOCN 1012, EOCN 1025 and EOCN 1027, and by Tohto Kasei Co.,Ltd. under the trade names of YDCN 701, YDCN 702, YDCN 703 and YDCN 704.

[0051] The hardener for the epoxy resin may be any hardener commonlyused for epoxy resins, and its examples include amines, polyamides, acidanhydrides, polysulfides, boron trifluoride and compounds having two ormore phenolic hydroxyl groups per molecule, such as bisphenol A,bisphenol F and bisphenol S. Having good resistance to electrolyticcorrosion on moisture absorption, phenol resins, such as phenol novolacresins, bisphenol novolac resins and cresol novolac resins, arepreferred.

[0052] Among the preferred hardeners, phenol novolac resins are marketedby Dainippon Ink & Chemicals, Inc. under the trade names of BARCAM TD2090, BARCAM TD-2131 and PLYORPHEN LF 2882, bisphenol novolac resins aremarketed by Dainippon Ink & Chemicals, Inc. under the trade namesof-PHENOLITE LF 2882, PHENOLITE LF 2822, PHENOLITE TD-2090, PHENOLITETD-2149, PHENOLITE VH 4150 and PHENOLITE VH 4170. Preferred phenolnovolac resins, bisphenol novolac resins and cresol novolac resins havea weight average molecular weight of 500 to 2,000, more preferably 700to 1,400.

[0053] The amount of the hardener is preferably 0.6 to 1.4 equivalents,more preferably 0.8 to 1.2 equivalents of groups reactive with the epoxygroups of the epoxy resin per equivalent of the epoxy groups of theepoxy resin. Less or excessive hardener may deteriorate heat resistance.

[0054] Examples of the high molecular weight resins being compatiblewith the epoxy resin and having a weight average molecular weight of30,000 or more include phenoxy resins, high molecular weight epoxyresins, ultra high molecular weight epoxy resins, rubbers having highlypolar functional groups and reactive rubbers having highly polarfunctional groups. To make the adhesive less tacky in B-stage and moreflexible after curing, the weight average molecular weight is 30,000 ormore. The high molecular weight resin being compatible with the epoxyresin and having a weight average molecular weight of 30,000 or morepreferably has a weight average molecular weight of 500,000 or less,more preferably 30,000 to 100,000. Resins having too large molecularweights lower the flowability. Examples of the reactive rubbers havinghighly polar functional groups include rubbers made by the addition ofhighly polar functional groups, such as carboxyl groups, to acrylicrubbers. Herein, the terms “being compatible with the epoxy resin” meanthat it forms a uniform blend together with the epoxy resin after curingwithout separating into two or more phases. To prevent the phasecontaining the epoxy resin as a main component (hereinafter referred toas epoxy resin phase) from lacking flexibility, decrease in tackinessand decrease in insulation due to cracking or the like, the amount ofthe high molecular weight resin being compatible with the epoxy resinand having a weight average molecular weight of 30,000 or more is 5parts by weight or more relative to 100 parts by weight of the total ofthe epoxy resin and the hardener, and 40 parts by weight or less toprevent decrease of the Tg of the epoxy resin phase, preferably 10 to 20parts by weight.

[0055] Phenoxy resins are marketed by Tohto Kasel Co., Ltd. under thetrade names of PHENOTOHTO YP-40 and PHNOTOHTO YP-50, by PhenoxyAssociate under the trade names of PKHC, PKHH and PKHJ. The highmolecular weight epoxy resins include high molecular weight epoxy resinshaving a molecular weight of 30,000 to 80,000 and ultra high molecularweight epoxy resins having a molecular weight of more than 80,000 (referto Japanese Patent Examined Publication Nos. 7-59617 (1995), 7-59618(1995), 7-59619 (1995), 7-59620 (1995), 7-64911 (1995) and 7-68327(1995)), all are produced by Hitachi Chemical Co., Ltd.). As a reactiverubber having highly polar functional group, a carboxyl group-havingacrylic rubber is marketed by Teikoku Kagaku Sangyo Co., Ltd. under thetrade name of HTR-860P.

[0056] An example of usable epoxidized acrylic copolymer having aglycidyl (meth)acrylate unit content of 0.5 to 6 wt. %, a Tg of −10° C.or higher and a weight average molecular weight of 100,000 or more isHTR-860P-3 (trade name) marketed by Teikoku Kagaku Sangyo Co., Ltd.Functional monomers of carboxylic acid type, such as acrylic acid, andof hydroxyl group type, such as hydroxymethyl (meth)acrylate, areunsuitable because they promote crosslinking, thereby decreasing bondingstrength due to gelation in a state of varnish and excessive curing in aB-stage state. The amount of glycidyl (meth)acrylate used as afunctional monomer is 0.5 to 6 wt. % in copolymerization ratio. It is0.5 wt. % or more to ensure heat resistance, and is 6 wt. % or less todecrease rubbers to be added and to increase the solid content of avarnish. In cases where it is more than 6 wt. %, a large amount of theepoxidized acrylic copolymer is necessary to lower the elastic modulusof cured adhesives. The epoxidized acrylic copolymer, having a highmolecular weight, increases the viscosity of adhesive varnishes with theincrease of its weight ratio. Varnishes of high viscosity are difficultto form into films and for this reason are diluted with a proper amountof a solvent to lower the viscosity. This results in the problems ofdecrease in the solid contents of the adhesive varnishes, increase inthe production of adhesive varnishes and the lowering of the productionefficiency. Examples of other units than the glycidyl (meth)acrylateunits include those derived from alkyl acrylates or alkyl methacrylatesboth having an alkyl group of 1 to 8 carbon atoms, such as methylacrylate and methyl methacrylate, or mixtures thereof with styrene oracrylonitrile. The mixing ratios thereof are selected in considerationof the Tg of the copolymer. The copolymer should have a Tg of −10° C. orhigher because B-stage adhesive films formed by using a copolymer with aTg of lower than −10° C. becomes too tacky to handle. The Tg ispreferably 40° C. or lower, more preferably −10° C. to 20° C. If the Tgis too high, the film may be broken on handling at room temperature.Examples of polymerization methods include pearl polymerization andsolution polymerization. Preferred copolymers are obtainable, forexample, by copolymerizing (a) 18 to 40 wt. % of acrylonitrile, (b) 0.5to 6 wt. % of glycidyl (meth)acrylate and (c) 54 to 80 wt. % of ethylacrylate, ethyl methacrylate, butyl acrylate or butyl methacrylate.

[0057] The epoxidized acrylic copolymer has a weight average molecularweight of 100,000 or more, particularly preferably 800,000 or more. Thereason is that such molecular weights cause not much decrease in thestrength and flexibility of films and not much increase in tackiness.The weight average molecular weight of the epoxidized acrylic copolymeris preferably 2,000,000 or less because larger molecular weights lowerflowability and make it difficult to fill wiring circuits.

[0058] The amount of the epoxidized acrylic copolymer preferably is 75parts by weight or more relative to 100 parts by weight of the total ofthe epoxy resin and the hardener to lower the elastic modulus and theflowability during molding, and is 300 parts by weight or less becauseexcessive epoxidized acrylic copolymer deteriorates processability athigh temperatures due to increase in the rubber phase and decrease inthe epoxy resin phase, and more preferably, it is 100 to 250 parts byweight.

[0059] The latent curing accelerator is a curing accelerator that canconsiderably lower the reaction rate of the adhesive at room temperaturewhile keeping the reaction rate at curing temperatures, and is a solidinsoluble in the epoxy resin at room temperature and is solubilized withheat to work as an accelerator. The latent curing accelerators usable inthe present invention include conventional latent curing accelerators,and typical but non-limitative examples include dicyanodiamide,dihydrazides, such as adipic dihydrazide, guanamic acid, melamic acid,adducts of an epoxide and an imidazole, adducts of an epoxide and adialkylamine, adducts of an amine and urea, thiourea or a derivativethereof (amine-ureido adduct latent curing accelerators) and adducts ofan amine and an isocyanate (amine-urethane adduct latent curingaccelerators). Preferred are those of adduct structures, which are lessactive at room temperature. Adduct structures are obtainable by theaddition reaction of catalytically active compounds with other variouscompounds, and an adduct wherein the catalytically active compound is anamine, such as an imidazole or a compound having primary, secondary ortertiary amino group is referred to as an amine adduct. Examples of theamine adducts to which different compounds are added include amine-epoxyadducts, amine-ureido adducts and amine-urethane adducts. The mostpreferred are amine-epoxy adducts, which do not foam on curing, havelower elasticity and give a curing product of the adhesive having goodheat resistance and moisture resistance. Those with long chain epoxidesare particularly preferable because of their high latency.

[0060] The amine-epoxy adduct latent curing accelerators usable in thepresent invention are insoluble in the epoxy resin at room temperatureand are solubilized with heat to work as accelerators, and are adductsobtainable by the reaction of an amine and an epoxide, and also includesuch adducts the surfaces of which are treated with an isocyanate or anacidic compound.

[0061] Non-limitative examples of the epoxides used for the productionof the amine-epoxy adduct latent curing accelerators includepolyglycidyl ethers obtainable by the reaction of a polyhydric phenol,such as bisphenol A, bisphenol F, catechol or resorcinol, or apolyhydric alcohol, such as glycerol or polyethylene glycol, withepichlorohydrin; glycidyl ether esters obtainable by the reaction of ahydroxycarboxylic acid, such as p-hydroxybenzoic acid orβ-hydroxynaphthoic acid, with epichlorohydrin; polyglycidyl estersobtainable by the reaction of a polycarboxylic acid, such as phthalicacid or terephthalic acid, with epichlorohydrin; glycidyl aminesobtainable, for example, by the reaction of 4,4′-diaminodiphenylmethaneor m-aminophenol. with epichlorohydrin; polyfunctional epoxides, such asepoxidized phenol novolac resins, epoxidized cresol novolac resins andepoxidized polyolefins; and monofunctional epoxides, such as butylglycidyl ether, phenyl glycidyl ether and glycidyl methacrylate.

[0062] The amines used for the production of the amine-epoxy adductlatent curing accelerators may be any ones which has per molecule one ormore active hydrogen addition-reactive with epoxy group and one or moresubstituent selected from primary amino group, secondary amino groupsand tertiary amino groups. Non-limitative examples of the amines includealiphatic amines, such as diethylenetriamine, triethylenetetramine,n-propylamine, 2-hydroxyethylaminopropylamine, cyclohexylamine,4,4′-diamino-dicyclohexylmethane; aromatic amines, such as4,4′-diaminodiphenylmethane and 2-methylaniline; and nitrogen-containingheterocyclic compounds, such as 2-ethyl-4-methylimidazole,2-methylimidazole, 2-ethyl-4-methylimidazoline, 2,4-dimethylimidazoline,piperidine and piperadine. Among these compounds, those having atertiary amino group give curing accelerators with very high latency,and non-limitative examples of such compounds include amine compounds,such as dimethylaminopropylamine, diehtylaminopropylamine,di-n-propylaminopropylamine, dibutylaminopropylamine,dimethylaminoethylamine, diethylaminoethylamine and N-methylpiperadine;and primary or secondary amines having a tertiary amino group inmolecule, for example imidazoles, such as 2-methylimidazole,2-ethylimidazole, 2-ethyl-4-methylimidazole and 2-phenylimidazole.

[0063] The above-described amines are also usable for the production ofthe amine-ureido adduct latent curing accelerators and amine-urethaneadduct latent curing accelerators.

[0064] Examples of the isocyanates used for the production of theamine-urethane adduct latent curing accelerators includepolyisocyanates, such as tolylene diisocyanates, diphenylmethanediisocyanates, naphthylene diisocyanates, xylylene diisocyanates,diphenyl sulfone diisocyanates, triphenylmethane diisocyanates,hexamethylene diisocyanate, 3-isocyanatomethyl-3,5,5-trimethylcyclohexylisocyanate, 3-isocyanatoethyl-3,5,5-trimethylcyclohexyl isocyanate,3-isocyanatoethyl-3,5,5-triethylcyclohexyl isocyanate, diphenylpropanediisocyanates, phenylene diisocyanates, cyclohexylylene diisocyanates,3,3′-diisocyanatodipropyl ether, triphenylmethane triisocyanates anddiphenyl ether-4,4′-diisocyanate; dimers and trimers thereof; andadducts of these polyisocyanates with polyhydric alcohols, such astrimethyrolpropane and glycerol.

[0065] Typical but non-limitative examples of the adduct-type curingaccelerators usable in the present invention are as follows. Examples ofthe amine-epoxy adducts are those marketed by Ajinomoto Co., Inc. underthe trade names of AMICURE PN-23, AMICURE MY-24, AMICURE MY-D andAMICURE MY-H, by A. C. R. Co., Ltd. under the trade names of HARDENERX-3615S and HARDENER X-3293S, by Asahi Chemical Industry Co., Ltd. underthe trade names of NOVACURE HX-3748 and NOVACURE HX-3088, by PacificAnchor Chemical under the trade names of ANCAMINE 2014 AS and ANCAMINE2014 FG. Examples of the amine-ureido adducts are those marketed by FujiKasei Co., Ltd. under the trade names of FUJICURE FXE-1000 and FUJICUREFXR-1030.

[0066] The amount of the latent curing accelerator is 0.1 to 20 parts byweight, preferably 1.0 to 15 parts by weight, relative to 100 parts byweight of the total of the epoxy resin and the hardener therefor, and ifless than 0.1 part by weight, curing rate will be too low to form a goodcured product of the adhesive, and if more than 20 parts by weight, theusable period will be problematically shortened.

[0067] The adhesive may contain a coupling agent to strengthen theinterfacial bonding between different materials. Examples of couplingagents include silane coupling agents, titanate coupling agents andaluminum coupling agents, with silane coupling agents preferred.

[0068] Examples of the silane coupling agents includeγ-glycidoxypropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane,γ-aminopropyltriethoxysilane, γ-ureidopropyltriethoxysilane andN-β-aminoethyl-γ-aminopropyltrimethoxysilane.

[0069] As to the above-described silane coupling agents,γ-glycidoxypropyltrimethoxysilane is marketed under the trade name ofNUC A-187, γ-mercaptopropyltrimethoxysilane under the trade name of NUCA-189, γ-aminopropyltriethoxysilane under the trade name of NUC A-1100,γ-ureidopropyltriethoxysilane under the trade name of NUC A-1160 andN-β-aminoethyl-γ-aminopropyltrimethoxysilane under the trade name of NUCA-1120, all by Japan Unicar Co., Ltd.

[0070] In view of effects, heat resistance and cost, the amount of thecoupling agent preferably is 0.1 to 10 parts by weight relative to 100parts by weight of resins.

[0071] Ion trapping agents may be added to improve the insulationreliability on moisture absorption by adsorbing ionic impurities. Inview of effects, heat resistance and cost, the amount of the iontrapping agents is preferably 1 to 10 parts by weight relative to 100parts by weight of the epoxy resin and the hardener therefor. As the iontrapping agents, known anti-copper-pollution agents for preventing theelution of ionized copper, such as triazine thiol compounds andbisphenol reductants, may be added. Examples of the bisphenol reductantsinclude 2,2′-methylene-bis-(4-methyl-6-tert-butyl phenol) and4,4′-thio-bis-(3-methyl-6-tert-butylphenol). Inorganic ion adsorbentsmay also be used. Examples of the inorganic ion adsorbents includezirconium compounds, antimony-bismuth compounds and magnesium-aluminumcompounds. An example of the anti-copper-hazard agents comprisingtriazine thiol compounds is JISNET DB (trade name) marketed by SankyoPharmaceutical Co., Ltd. An example of the anti-copper-pollution agentscomprising bisphenol reductants is YOSHINOX BB (trade name) marketed byYoshitomi Pharmaceutical Co., Ltd. Various inorganic ion adsorbents aremarketed by Toagosei Chemical Co., Ltd. under the trade name of IXE.

[0072] The adhesive of the present invention preferably contains aninorganic filler for improving the processability and thermalconductivity of the adhesive, controlling the melt viscosity and givingthixotropy. Examples of inorganic fillers include aluminum hydroxide,magnesium hydroxide, calcium carbonate, magnesium carbonate, calciumsilicate, magnesium silicate, calcium oxide, magnesium oxide, alumina,aluminum nitride, aluminum borate whisker, boron nitride, crystallinesilica, amorphous silica and antimony oxide. Alumina, aluminum nitride,boron nitride, crystalline silica and amorphous silica are suitable forimproving thermal conductivity. Aluminum hydroxide, magnesium hydroxide,calcium carbonate, magnesium carbonate, calcium silicate, magnesiumsilicate, calcium oxide, magnesium oxide, alumina, crystalline silicaand amorphous silica are suitable for controlling melt viscosity andgiving thixotropy. Alumina, silica, aluminum hydroxide and antimonyoxide are suitable for improving moisture resistance in addition to theabove properties.

[0073] The content of the inorganic filler is preferably 1 to 20 partsby volume relative to 100 parts by volume of the resin content of theadhesive. The reason is that contents of 1 part by volume or more arepreferable to make effects, and contents of 20 parts by volume or lessare preferable to prevent the problems resulting from large contents,such as increase in the storage modulus of the adhesive, decrease inadhesion and deterioration in electrical properties due to voids.

[0074] We also have found that the storage stability of adhesives andadhesive films can be improved by selectively putting curingaccelerators into a discontinuously dispersed resin phase. For thispurpose, the adhesive B should be an adhesive composition comprising twokinds of resins separating into two phases in a B-stage state, ahardener and a curing accelerator, and the curing accelerator should becompatible with the disperse phase in a B-stage state and separates fromthe continuous phase.

[0075] Examples of the resins to be used to form the disperse phaseinclude epoxy resins, cyanate ester resins, cyanate resins, siliconeresins, acrylic rubbers having functional groups, such as epoxy groupsor carboxyl groups, butadiene rubbers having functional groups, such asepoxy groups or carboxyl groups and modified resins, such assilicone-modified polyamide-imides. Epoxy resins are preferred for theirhigh adhesion and good heat resistance. Usable epoxy resins are the sameas those described above. Usable hardeners for epoxy resins are also thesame as those described above. The amounts and ratios thereof are thesame as those described above.

[0076] Examples of the resins which separate from the resin phase in aB-stage state include acrylic rubbers which are copolymers of an acrylicester or methacrylic ester with acrylonitrile, butadiene rubberscontaining styrene units or acrylonitrile units, silicone resins andmodified resins, such as silicone-modified polyamide-imides. To form afilm with good processability, it is preferable to use a high molecularweight component having a weight average molecular weight of 100,000 ormore. To increase adhesion and heat resistance, it is particularlypreferable to use an acrylic copolymer having a glycidyl methacrylate orglycidyl acrylate unit content of 2 to 6 wt. % and a Tg of −10° C. orhigher and a weight average molecular weight of 100,000 or more(particularly preferably 800,000 or more and preferably 2,000,000 orless).

[0077] Among the acrylic copolymers exemplified for the adhesive A,those having a glycidyl (meth)acrylate unit content of 2 to 6 wt. % canbe used as the acrylic copolymers having a glycidyl methacrylate orglycidyl acrylate unit content of 2 to 6 wt. % and a Tg of −10° C. orhigher and a weight average molecular weight of 100,000 or more(particularly preferably 800,000 or more).

[0078] The resins for forming the resin phases should separate intoseparate phases in a B-stage state, and one resin has to form adiscontinuous disperse phase, other resin a continuous phase. TheB-stage state herein means a state wherein, as measured by using a DSC,10 to 40% of heat to be generated by the complete curing of an uncuredcomposition has been generated.

[0079] The preferred amount of the resin for forming a continuous phasein a B-stage state is generally 20 to 85 wt. % of the total of theresins forming the disperse phase and the continuous phase.

[0080] The curing accelerator should be compatible with the island-likedisperse phase discontinuously dispersed in a B-stage state and separatefrom the sea-like phase. It preferably is, in polarity and molecularstructure, similar to the island-like phase and largely different fromthe other phase. For example, in cases where the discontinuouslydispersed island-like resin phase comprises an epoxy resin and ahardener as main components and the other phase is an acrylic rubber,the curing accelerator is preferably an adduct of an epoxide and animidazole or an adduct of an epoxide and a dialkylamine. Particularlypreferred are adducts of long chain epoxides. In view of low activity atroom temperature, preferred are curing accelerators of adductstructures, such as amine-epoxy adducts, amine-ureido adducts andamine-urethane adducts. The most preferred are amine-epoxy adducts,which do not foam on curing, have lower elasticity and give a curingproduct of the adhesive having good heat resistance and moistureresistance.

[0081] Typical examples of the amine-epoxy adduct latent curingaccelerators and other adduct curing accelerators are as exemplifiedabove.

[0082] The amount of curing accelerators (including latent curingaccelerators) is preferably 0.1 to 20 parts by weight, more preferably1.0 to 15 parts by weight, relative to 100 parts by weight of the totalof the resin and the hardener in the disperse phase. An amount of lessthan 0.1 part by weight may lower the curing rate, and that of more than20 parts by weight may shorten the usable period.

[0083] Preferred curing accelerators are the adduct-type of latentcuring accelerators as described above, and are preferably used incombination of imidazoles in proper ratios for keeping the desiredstorage stability.

[0084] Examples of the imidazoles include 2-methylimidazole,2-ethyl-4-methylimidazole, 1-cyanoethyl-2-phenylimidazole and1-cyanoethyl-2-phenylimidaolium trimellitate. Such imidazoles aremarketed by Shikoku Kasei Kogyo Co., Ltd. under the trade names of2E4MZ, 2PZ-CN and 2PZ-CSN.

[0085] Fillers may additionally be added to control the flowability andto improve moisture resistance. Examples of such fillers include silicaand diantimony trioxide.

[0086] The adhesive may contain coupling agents to strengthen theinterfacial bonding between different materials. Ion trapping agents mayfurther be added to improve the insulation reliability on moistureabsorption by adsorbing ionic impurities.

[0087] The amount of coupling agents preferably is 0.1 to 10 wt. % ofthe total of the resin components forming the disperse phase and thecontinuous phase, respectively, and the hardener component.

[0088] The amount of ion trapping agents preferably is 1 to 10 wt. % ofthe total of the resin components forming the disperse phase and thecontinuous phase, respectively, and the hardener component.

[0089] The effect of selectively putting the curing accelerator into thediscontinuously dispersed resin phase is not clear, but is supposed asfollows. Great part of the curing accelerator is contained in theisland-like disperse phase, and the continuous phase contains littlecuring accelerator. The flowability is not affected very much by thecuring proceeding in the disperse phase during storage, while, at curingtemperatures, the continuous phase is presumed to undergo curing by thereaction thereof with the active groups resulting from the reaction thatstarted in the disperse phase.

[0090] The film-form adhesive member of the present invention isobtainable by dissolving or dispersing the components of the adhesive ina solvent to form a varnish, which is applied to a carrier film andheated to remove the solvent, to form an adhesive layer on the carrierfilm. The heating temperature is preferably 100 to 180° C., morepreferably 130 to 160° C., and the heating time is preferably 3 to 15minutes, more preferably 4 to 10 minutes. It is preferable that theremoval of the solvent by heating is carried out so that the adhesive ispartially cured to generate 10 to 40% of the heat to be generated bycomplete curing thereof as measured by DSC (differential scanningthermal analysis). The resulting film-form adhesive preferably has aresidual solvent content of 5 wt. % or less.

[0091] Examples of usable carrier films are plastic films, such aspolytetrafluoroethylene films, polyethyleneterephthalate films,release-treated polyethyleneterephthalate films, polyethylene films,polypropylene films, polymethylpentene films and polyimide films. Whenthe film-form adhesive member is used, the carrier film may be removedto use the adhesive film alone, or may be used together with theadhesive film and removed later.

[0092] As to Examples of the carrier films to be used in the presentinvention, polyimide films are marketed by Toray DuPont Co., Ltd. underthe trade name of CAPTON, and by Kanegafuchi Chemical Industry Co., Ltd.under the trade name of APICAL. Polyethyleneterephthalate films aremarketed by Toray DuPont Co., Ltd. under the trade name of RUMILAR, andby Teijin Ltd. under the trade name of PULEX.

[0093] The varnish preferably is prepared by using a solvent of arelatively low boiling point, such as methyl ethyl ketone, acetone,methyl isobutyl ketone, 2-ethoxyethanol, toluene, butyl cellosolve,methanol, ethanol or 2-methoxyethanol. Solvents of high boiling pointsmay be added to improve the coating properties. Examples of solvents ofhigh boiling points include dimethylacetamide, dimethylformamide,methylpyrrolidone and cyclohexanone.

[0094] To disperse a inorganic filler, the varnish can be prepared byusing a mixing and kneading machine, a triple roll, a bead mill or acombination thereof. The mixing time can be shortened by mixing a fillerwith low molecular weight components and then mixing thereto highmolecular weight components. After preparation, the varnish preferablyis degassed under vacuum to remove bubbles.

[0095] The thickness of the adhesive member consisting of a film-formadhesive is not limited but preferably is 25 to 250 μm. Adhesive membersthinner than 25 μm cannot release stress effectively, and thick ones arenot economical.

[0096] Two or more adhesive films may be stuck together to obtain anadhesive member of the desired thickness. In such a case, the adhesivefilms should be stuck so as not to be peeled off from each other.

[0097] The adhesive member of the present invention may comprise a corematerial and an adhesive layer formed on each side of the core material.The thickness of the core material is not limited but preferably is 5 to200 μm. The thickness of each adhesive layer formed on each side of thecore material is not limited but preferably is 10 to 200 μm. Adhesivelayers thinner than the range cannot release stress effectively, andthicker ones are not economical.

[0098] The core material to be used in the present invention preferablyis a heat resistant thermoplastic film made of a heat resistant polymer,a liquid crystalline polymer or a fluorinated polymer, andpreferred-examples are polyamideimides, polyimides, polyether imides,polyether sulfones, aromatic polyesters, polytetrafluoroethylenes,ethylene tetrafluoroethylene copolymers,tetrafluoroethylene-hexafluoropropylene copolymers andtetrafluoroethylene-perfluoroalkyl vinyl ether copolymers. The corematerial may also be a porous film for lowering the elastic modulus ofthe adhesive member. The core material preferably has a softeningtemperature of 260° C. or higher. In cases where the core material is athermoplastic film with a softening temperature of lower than 260° C.,it may be peeled off from the adhesive at high temperatures on solderreflow or the like.

[0099] Polyimide films are marketed by Ube Industries, Ltd. under thetrade name of UPILEX, by Toray DuPont Co., Ltd. under the trade name ofCAPTON, and by Kanegafuchi Chemical Industry Co., Ltd. under the tradename of APICAL. Polytetrafluoroethylene films are marketed byMitsui•DuPont Fluorochemicals Co., Ltd. under the trade name of TEFLON,and by Daikin Industries, Ltd. under the trade name of POLYFLON.Ethylene tetrafluoroethylene copolymer films are marketed by Asahi GlassCo., Ltd. under the trade name of AFLON COP, and by Daikin Industries,Ltd. under the trade name of NEOFLON ETFE.Tetrafluoroethylene-hexafluoropropylene copolymer films are marketed byMitsui•DuPont Fluorochemicals Co., Ltd. under the trade name of TEFLONFEP, and by Daikin Industries, Ltd. under the trade name of NEOFLON FEP.Tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer films aremarketed by Mitsui DuPont Fluorochemicals Co., Ltd. under the trade nameof TEFLON PFA, and by Daikin Industries, Ltd. under the trade name ofNEOFLON PFA. Liquid crystalline polymer films are marketed by Kuraray,Co., Ltd. under the trade name of VECTRAN. Porouspolytetrafluoroethylene films are marketed by Sumitomo ElectricIndustries, Ltd. under the trade name of POREFLON, and by Japan GoatexCo., Ltd. under the trade name of GOATEX.

[0100] Each of the adhesive layers on both sides of the core materialmay be formed by dissolving or dispersing the components of the adhesivein a solvent to prepare a varnish, applying the varnish onto a heatresistant thermoplastic film used as the core material and removing thesolvent by heating, to form an adhesive layer on the heat resistantthermoplastic film. By conducting the process on both sides of the heatresistant thermoplastic film, an adhesive member wherein an adhesivelayer is formed on each side of a core material can be produced. Thesurfaces of the adhesive layers on both sides preferably are protectedwith cover films to prevent blocking. The cover films are optionalbecause, in cases where there is no possibility of blocking, it ispreferable to use no cover films in view of economy.

[0101] Alternatively, the adhesive member wherein an adhesive layer isformed on each side of a core material can be produced by dissolving ordispersing the components of the adhesive in a solvent to form avarnish, applying the varnish onto a carrier film as described above,removing the solvent by heating to form an adhesive layer on the carrierfilm, and applying the adhesive layer onto each side of a core material.In this case, the carrier film can be used as a cover film.

[0102] As for the adhesive member consisting of a film-form adhesive is,the adhesive layer formed on each side of the core material preferablyhas generated 10 to 40% of heat to be generated by complete curingthereof as measured by DSC.

[0103] The cured product of the adhesive of the present inventionpreferably has a storage modulus of as low as 20 to 2,000 MPa at 25° C.,and 3 to 50 MPa at 260° C., as measured with a dynamic viscoelasticitymeasuring apparatus. Herein, the measurement of the storage modulus wasconducted in a temperature dependent measuring mode on the cured productof an adhesive applied with a tension, at a frequency of 10 Hz, within atemperature range of −50° C. to 300° C. raised at a rate of 5 to 10°C./min. Cured products having a storage modulus of more than 2,000 MPaat 25° C. and more than 50 MPa at 260° C. are less effective inreleasing the thermal stress resulting from the difference incoefficient of thermal expansion between a semiconductor chip and aninterposer as an interconnecting substrate, and may cause peeling orcracking. Adhesives giving cured products having a storage modulus ofless than 20 MPa at 25° C. may be difficult to handle and form adhesivelayers lacking accuracy in thickness, and cured products having astorage modulus of less than 3 MPa at 260° C. may cause reflow cracking.

[0104] The interconnecting substrate for semiconductor mounting of thepresent invention comprises an interconnecting substrate and theadhesive member of the present invention stuck on the semiconductorchip-mounting surface of the interconnecting substrate.

[0105] The interconnecting substrate used in the interconnectingsubstrate for semiconductor mounting of the present invention is notlimited in material, and, for example, may be a ceramic substrate or anorganic substrate. Examples of usable ceramic substrates include aluminasubstrates and aluminum nitride substrates. Examples of usable organicsubstrates include FR-4 substrates comprising a glass cloth impregnatedwith an epoxy resin, BT substrates comprising glass cloth impregnatedwith a bismaleimide-triazine resin and polyimide film substrates whereina polyimide film is used as a base material.

[0106] The interconnecting pattern may be of any one of a single-sidedinterconnecting line, a double-sided interconnecting line or amultilayered interconnecting line, and may optionally be provided withelectrically connected through or non-through holes.

[0107] In cases where the interconnecting line is exposed on the outersurface of a semiconductor device, it preferably is coated with aprotective resin layer.

[0108] According to a general but non-limitative method, the adhesivemember is cut into a strip of a desired form, which is then stuck on aprescribed position of an interconnecting substrate with heat andpressure.

[0109] The semiconductor device of the present invention may have anystructure, which contains a semiconductor chip and an interconnectingsubstrate bonded together by using the adhesive member of the presentinvention.

[0110] For example, the semiconductor device of the present inventionmay have a structure wherein the electrodes of the semiconductor chipand the interconnecting substrate are connected by wire bonding, or astructure wherein the electrodes of the semiconductor chip and theinterconnecting substrate are connected by the inner lead bonding oftape automated bonding (TAB), and is effective irrespective ofstructure.

[0111]FIG. 1 to FIG. 3 show the processes for constructingnon-limitative examples of the semiconductor devices of the presentinvention by using adhesive members.

[0112] The adhesive member may either be a film-form adhesive 1 as shownin FIG. 1(a) or comprise a core material 2 and a layer of an adhesive 1provided on each side of the core material 2 as shown in FIG. 1(b). Anadhesive member cut out into a prescribed size is stuck on aninterconnecting substrate 4 as shown in FIG. 2(a) and FIG. 2(b) on theside. bearing an interconnecting line 3 by heating and pressing, forexample, at 100 to 150° C. at 0.01 to 3 MPa for 0.5 to 10 seconds, togive an adhesive member-bearing interconnecting substrate forsemiconductor mounting. A semiconductor chip 5 is stuck on the otherside of the adhesive member than the side stuck on the interconnectingsubstrate 4 by heating and pressing, for example, at 120 to 200° C. at0.1 to 3 MPa for 1 to 10 seconds, and the layers of the adhesive 1 ofthe adhesive members are cured by heating at 150 to 200° C. for 0.5 to 2hours. Thereafter, as shown in FIG. 3(a) and FIG. 3(b), the pads on thesemiconductor chip 5 and the interconnecting line 3 on theinterconnecting substrate 4 are connected by bonding wires 6, or, asshown in FIG. 3(c) and FIG. 3(d), the inner leads 6′ of theinterconnecting substrate 4 are bonded to the pads of the semiconductorchip 5. Then, sealing with a sealing material 7 and fixing of solderballs as leads for external connection 8 are carried out, to give asemiconductor device.

[0113] In the process described above, the temperature for sticking theadhesive member on the interconnecting substrate 4 on the side bearingthe interconnecting line 3 is generally lower than the temperature forsticking the semiconductor chip 5.

[0114] Though a semiconductor chip and an interconnecting substratewhich are similar in area generate a large thermal stress between them,the adhesive member for electronic parts used in the semiconductordevice of the present invention has a low elastic modulus and releasesthe thermal stress, thereby ensuring reliability. Further thesemiconductor device can be made flame-resistant by using aflame-resistant adhesive member. These effects are significant when thesemiconductor chip has an area of 70% or more of the area of theinterconnecting substrate. The areas of a semiconductor chip and aninterconnecting substrate mean the areas of their surfaces facing eachother. Such a semiconductor device containing a semiconductor chip andan interconnecting substrate having similar areas generally has leadsfor external connection of an area-form.

[0115] Semiconductor devices wherein a semiconductor chip and aninterconnecting substrate were bonded by using the adhesive member ofthe present invention were excellent in reflow resistance, heat-cycletest and moisture resistance (resistance to PCT). Further, because theadhesive has a long usable period, semiconductor devices produced byusing an adhesive that had been stored for three months at 25° C. andsemiconductor devices produced by using a fresh adhesive exhibitedsubstantially equal characteristics.

[0116] Herein, the weight average molecular weight is measured throughgel permeation chromatography, based on the calibration curve of astandard, polystyrene.

EXAMPLES

[0117] Hereinafter, the present invention will be described in moredetail referring to working examples.

[0118] (Preparation of Adhesive Varnish 1)

[0119] Methyl ethyl ketone was added to a composition comprising 45parts by weight of a bisphenol A epoxy resin (epoxy equivalent weight:175, trade name: YD-8125 produced by Tohto Kasei Co., Ltd.) and 15 partsby weight of a cresol novolac epoxy resin (epoxy equivalent weight: 210,trade name: YDCN-703 produced by Tohto Kasei Co., Ltd.) as epoxy resins,40 parts by weight of a phenol novolac resin (trade name: PLYORPHEN LF2882 produced by Dainippon Ink & Chemicals, Inc.) as a hardener for theepoxy resins, 220 parts by weight of an epoxidized acrylic rubber(molecular weight: 1,000,000, glycidyl methacrylate unit content: 1 wt.%, Tg: −70° C., trade name: HTR-860P-3 produced by Teikoku Kagaku SangyoCo., Ltd.) as an epoxidized acrylic copolymer and 5 parts by weight ofan amine-ureido adduct curing accelerator (trade name: FUJICURE FXR-1030produced by Fuji Kasei Co., Ltd.) as a latent curing accelerator, mixedwith stirring and degassed under vacuum. An adhesive film was producedby applying the resulting adhesive varnish onto a release-treatedpolyethyleneterephthalate film of 75 μm thick, and drying with heat at140° C. for 5 minutes, to form a 80 μm-thick coating. After the adhesivefilm was cured by heating at 170° C. for one hour, its storage moduluswas measured by using a dynamic viscoelasticity measuring apparatus(DVE-V4, produced by Rheology Co., Ltd.) (sample size: 20 mm long, 4 mmwide and 80 μm thick, heating rate: 5° C./min, tension mode, 10 Hz,automated static loading) to be 600 MPa at 25° C. and 5 MPa at 260° C.The adhesive varnish had a solid content of 32 wt. %. The adhesivevarnish was adjusted to the solid content so that it had a viscosity of100 poises (25° C.), because higher solid contents result in higherviscosities so that the thickness varies widely (the same reason appliescorrespondingly to the following).

[0120] (Preparation of Adhesive Varnish 2)

[0121] Adhesive varnish 2 was prepared in the same manner as in thepreparation of adhesive varnish 1 except that the amine-ureido adductcuring accelerator as a latent curing accelerator was replaced by 5parts by weight of an amine-epoxy adduct curing accelerator (trade name:AMICURE MY-24 produced by Ajinomoto Co., Inc.).

[0122] An adhesive film was produced by using adhesive varnish 2 in thesame manner as in the preparation of adhesive varnish 1. The storagemodulus of the adhesive film was measured by using a dynamicviscoelasticity measuring apparatus in the same manner as describedabove, to be 360 MPa at 25° C., and 4 MPa at 260° C. Adhesive varnish 2had a solid content of 30 wt. %.

[0123] (Preparation of Adhesive Varnish 3)

[0124] Adhesive varnish 3 was prepared in the same manner as in thepreparation of adhesive varnish 2 except that the amount of theamine-epoxy adduct curing accelerator as a latent curing accelerator waschanged to 3 parts by weight.

[0125] An adhesive film was produced by using adhesive varnish 3 in thesame manner as in the preparation of adhesive varnish 1 except that thetemperature of the drying for forming a film was changed from 140° C. to160° C. The storage modulus of the adhesive film was measured by using adynamic viscoelasticity measuring apparatus in the same manner asdescribed above, to be 360 MPa at 25° C., and 4 MPa at 260° C. Adhesivevarnish 3 had a solid content of 28 wt. %.

[0126] (Preparation of Adhesive Varnish 4)

[0127] Adhesive varnish 4 was prepared in the same manner as in thepreparation of adhesive varnish 2 except that the amount of theamine-epoxy adduct curing accelerator as a latent curing accelerator waschanged to 10 parts by weight.

[0128] An adhesive film was produced by using adhesive varnish 4 in thesame manner as in the preparation of adhesive varnish 1 except that thetemperature of the drying for forming a film was changed from 140° C. to120° C. The storage modulus of the adhesive film was measured by using adynamic viscoelasticity measuring apparatus in the same manner asdescribed above, to be 360 MPa at 25° C., and 4 MPa at 260° C. Adhesivevarnish 4 had a solid content of 28 wt. %.

[0129] (Preparation Of Adhesive Varnish 5)

[0130] Adhesive varnish 5 was prepared in the same manner as in thepreparation of adhesive varnish 1 except that the amine-ureido adductcuring accelerator as a latent curing accelerator was replaced by 0.5parts by weight of 2-phenylimidazole.

[0131] An adhesive film was produced by using adhesive varnish 5 in thesame manner as in the preparation of adhesive varnish 1. The storagemodulus of the adhesive film was measured by using a dynamicviscoelasticity measuring apparatus in the same manner as describedabove, to be 360 MPa at 25° C., and 4 MPa at 260° C. Adhesive varnish 5had a solid content of 28 wt. %.

Example 1

[0132] An adhesive film bearing a carrier film was produced by applyingadhesive varnish 1 onto a release-treated polyethyleneterephthalate filmof 75 μm thick and drying with heat at 140° C. for 5 minutes to form a75 μm-thick coating of a B-stage state. Two sheets of the adhesive filmwere stuck together by using a hot roll laminator at a temperature of110° C., at a pressure of 0.3 MPa and at a rate of 0.3 m/min., to givean adhesive member in a form of a single-layer film of 150 μm thick.

[0133] The curing degree of the adhesive in the above-described statewas determined by using a DSC (a 912-type DSC produced by E. I. DuPontde Nemours and Company) (heating rate: 10° C./min.) to be such that ithad generated 20% of the heat to be generated by complete curing. Theresidual solvent content of the adhesive alone was determined to be 1.5wt. % based on the change in weight before and after heating at 120° C.for 60 minutes.

Example 2

[0134] An adhesive member in a form of a single-layer film was producedin the same manner as in Example 1, except that adhesive varnish 1 wasreplaced by adhesive varnish 2.

[0135] The curing degree of the adhesive in the above-described statewas determined by using a DSC (a 912-type DSC produced by E. I. DuPontde Nemours and Company) (heating rate: 10° C./min.) to be such that ithad generated 20% of the heat to be generated by complete curing. Theresidual solvent content was 1.4 wt. %.

Example 3

[0136] Adhesive varnish 2 was applied onto a 25 μm-thick polyimide film(trade name: UPILEX SGA-25 produced Ube Industries, Ltd.) and dried withheat at 120° C. for 5 minutes to form a 50 μm-thick coating of a B-stagestate. The same varnish was then applied onto the polyimide film on theside bearing no adhesive layer and dried with heat at 140° C. for 5minutes to form a 70 μm-thick coating of a B-stage state, to give anadhesive member comprising the polyimide film used as a core materialbearing an adhesive layer on each side.

[0137] The curing degree of the adhesive in the above-described statewas determined by using a DSC (a 912-type DSC produced by E. I. DuPontde Nemours and Company) (heating rate: 10° C./min.) to be such that ithad generated in the 50 μm-thick layer 25% of the heat to be generatedby complete curing, and in the 75 μm-thick layer, 20%. The adhesive inboth layers had residual solvent contents of 1.3 to 1.6 wt. %.

Example 4

[0138] An adhesive film bearing a carrier film was produced by applyingadhesive varnish 2 onto a release-treated polyethyleneterephthalate filmof 75 μm thick and drying with heat at 140° C. for 5 minutes to form a75 μm-thick coating of a B-stage state. The adhesive film was stuck onboth sides of a 25 μm-thick polyimide film (trade name: UPILEX SGA-25produced by Ube Industries, Ltd.) by using a hot roll laminator at atemperature of 110° C., at a pressure of 0.3 MPa and at a rate of 0.2m/min., to give an adhesive member comprising the polyimide film as acore material bearing an adhesive layer on each side.

[0139] The curing degree of the adhesive in the above-described statewas determined by using a DSC (a 912-type DSC produced by E. I. DuPontde Nemours and Company) (heating rate: 10° C./min.) to be such that ithad generated in both layers 20% of the heat to be generated by completecuring. The residual solvent content was 1.4 wt. %.

Example 5

[0140] An adhesive member comprising a liquid crystalline polymer filmas a core material bearing an adhesive layer on each side was producedin the same manner as in Example 4, except that the polyimide film as acore material was replaced by a 25 μm-thick liquid crystalline polymerfilm (trade name: VECTRAN LCP-A produced by Kuraray, Co., Ltd.).

[0141] The curing degree of the adhesive in the above-described statewas determined by using a DSC (a 912-type DSC produced by E. I. DuPontde Nemours and Company) (heating rate: 10° C./min.) to be such that ithad generated in both layers 20% of the heat to be generated by completecuring. The residual solvent content was 1.4 wt. %.

Example 6

[0142] An adhesive member comprising atetrafluoroethylene-hexafluoropropylene copolymer film bearing anadhesive layer on each side was produced in the same manner as inExample 4, except that the polyimide film as a core material wasreplaced by a 25 μm-thick tetrafluoroethylene-hexafluoropropylenecopolymer film (trade name: TEFLON FEP produced by Mitsui DuPontFluorochemicals Co., Ltd.). The tetrafluoroethylene-hexafluoropropylenecopolymer film used had both surfaces chemically treated with TETRAETCH(trade name, produced by Kabushiki Kaisha Junkosha) to increase adhesionby increasing wettability.

[0143] The curing degree of the adhesive in the above-described statewas determined by using a DSC (a 912-type DSC produced by E. I. DuPontde Nemours and Company) (heating rate: 10° C./min.) to be such that ithad generated in both layers 20% of the heat to be generated by completecuring. The residual solvent content was 1.5 wt. %.

Example 7

[0144] An adhesive member of a single-layer film form bearing a carrierfilm was produced by applying adhesive varnish 2 onto a release-treatedpolyethyleneterephthalate film of 75 μm thick and drying with heat at140° C. for 5 minutes to form a 60 μm-thick coating of a B-stage state.The single-layer film was stuck on both sides of a 100 μm-thick porouspolytetrafluoroethylene film (trade name: WP-100-100 produced bySumitomo Electric Industries, Ltd.) by using a hot roll laminator at atemperature of 110° C., at a pressure of 0.3 MPa and at a rate of 0.2m/min., to give an adhesive member comprising the porouspolytetrafluoroethylene film as a core material bearing an adhesivelayer on each side.

[0145] The curing degree of the adhesive in the above-described statewas determined by using a DSC (a 912-type DSC produced by E. I. DuPontde Nemours and Company) (heating rate: 10° C./min.) to be such that ithad generated in both layers 20% of the heat to be generated by completecuring. The residual solvent content was 1.4 wt. %.

Example 8

[0146] An adhesive member of a single-layer film form was produced inthe same manner as in Example 1, except that adhesive varnish 1 wasreplaced by adhesive varnish 3, and the temperature of the drying forforming a film was changed from 140° C. to 160° C.

[0147] The curing degree of the adhesive in the above-described statewas determined by using a DSC (a 912-type DSC produced by E. I. DuPontde Nemours and Company) (heating rate: 10° C./min.) to be such that ithad generated 20% of the heat to be generated by complete curing.

Example 9

[0148] An adhesive member of a single-layer film form was produced inthe same manner as in Example 1, except that adhesive varnish 1 wasreplaced by adhesive varnish 4, and the temperature of the drying forforming a film was changed from 140° C. to 120° C.

[0149] The curing degree of the adhesive in the above-described statewas determined by using a DSC (a 912-type DSC produced by E. I. DuPontde Nemours and Company) (heating rate: 10° C./min.) to be such that ithad generated 20% of the heat to be generated by complete curing.

Reference Example 1

[0150] An adhesive member of a single-layer film form was produced inthe same manner as in Example 1, except that adhesive varnish 1 wasreplaced by adhesive varnish 5.

[0151] The curing degree of the adhesive in the above-described statewas determined by using a DSC (a 912-type DSC produced by E. I. DuPontde Nemours and Company) (heating rate: 10° C./min.) to be such that ithad generated 20% of the heat to be generated by complete curing.

[0152] By using the obtained adhesive members, semiconductor devicesamples (solder balls were formed on one side) as shown in FIG. 3(c) andFIG. 3(d) were produced by sticking with an adhesive member asemiconductor chip on an interconnecting substrate the base material ofwhich was a 25 μm-thick polyimide film (sticking conditions:temperature: 160° C., pressure: 1.5 MPa, time: 3 seconds), and wereexamined for heat resistance, flame-resistance, moisture resistance andfoaming. The heat resistance was evaluated by reflow cracking resistanceand a thermal cycle test. The reflow cracking resistance was evaluatedby subjecting twice the samples to a treatment wherein they were passedthrough an IR reflow furnace heated to keep the surface temperature ofthe samples to 240° C. for 20 seconds and cooled by allowing them tostand at room temperature, and then observing the inside of the samplesfor cracks visually and with an ultrasonic microscope. The mark ◯ meansa sample not cracked, and X means a sample cracked. The resistance tothermal cycles was evaluated by allowing the samples to stand in anatmosphere of −55° C. for 30 minutes and then allowing them to stand inan atmosphere of 125° C. for 30 minutes in one cycle. After 1,000cycles, the samples were observed with an ultrasonic microscope, andrated as ◯ when breakage, such as peeling or cracks, was not observed,and as X when breakage was observed. The moisture resistant wasevaluated by observing the samples for peeling after the samples weretreated for 72 hours in an atmosphere of a temperature of 121° C., ahumidity of 100% and 2 atm (pressure cooker test, PCT treatment). Themark ◯ means a sample wherein the peeling of the bonding member was notobserved, and X means a sample wherein the peeling was observed. Foamingwas observed with an ultrasonic microscope, and samples wherein theadhesive members did not foam were rated as ◯, and those wherein theadhesive members foamed as X. The usable period was evaluated byproducing semiconductor devices of the same types by using the adhesivemembers after they were stored at 25° C. for 3 months, and observing theadhesives filling circuits with an ultrasonic microscope. The sampleswherein no vacant space was observed between the adhesives and theinterconnecting lines were rated as ◯, and those wherein such vacantspaces were observed were rated as X. The results are given in Table 1.TABLE 1 Result of Evaluation Ref. Ex. Example Nos. No. 1 2 3 4 5 6 7 8 91 Heat Reflow crack resistance ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ resistance Thermalcycle resistance ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ Moisture resistance ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯◯ ◯ Foaming X ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ Usable period ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ X

[0153] In Example 1 wherein an amine-ureido adduct latent curingaccelerator was used, the usable period was long, but foaming occurredon curing. In Examples 2 to 9 wherein an amine-epoxy adduct latentcuring accelerator was used, good results of a long usable period and nofoaming on curing were obtained. In these Examples, the curing productsof adhesives had the preferred storage modulus at 25° C. and 260° C. asspecified in the present invention, and the semiconductor devices usingthe adhesive members exhibited good results in reflow crack resistance,thermal cycle resistance and moisture resistance. The adhesive membersused in Examples 3 to 7, which had core materials, had goodprocessability.

[0154] In Reference Example 1 wherein an imidazole having no adduct wasused as a curing accelerator, the usable period was short.

Example 10

[0155] Methyl ethyl ketone was added to a composition comprising 45parts by weight of a bisphenol A epoxy resin (epoxy equivalent weight:190, trade name: EPIKOTE 828 produced by Yuka Shell Epoxy Co., Ltd.) and15 parts by weight of a cresol novolac epoxy resin (epoxy equivalentweight: 195, trade name: ESCN 195 produced by Sumitomo Chemical Co.,Ltd.) as epoxy resins, 40 parts by weight of a phenol novolac resin(trade name: PLYORPHEN LF2882 produced by Dainippon Ink & Chemicals,Inc.) as a hardener for the epoxy resins and 0.7 parts by weight ofγ-glycidoxypropyltrimethoxysilane (trade name: NUCA-187 produced byNippon Yunicar Kabushiki Kaisha) as a silane coupling agent and mixedwith stirring. To the mixture were added 150 parts by weight of anepoxidized acrylic copolymer having a glycidyl methacrylate or glycidylacrylate unit content of 2 to 6 wt. % (weight average molecular weight:1,000,000, trade name: HTR-860P-3 produced by Teikoku Kagaku Sangyo Co.,Ltd.) and 4 parts by weight of an amine-epoxy adduct (trade name:AMICURE MY-24 produced by Ajinomoto Co., Inc.) as a curing accelerator,and the mixture was stirred with an agitating motor for 30 minutes, toobtain a varnish. A 75 μm-thick coating of a B-stage state was formedfrom the varnish, to produce an adhesive film bearing a carrier film (arelease treated polyethyleneterephthalate film, thickness: 75 μm)(drying conditions: temperature: 140° C., time: 5 minutes). In theadhesive of the B-stage state, AMICURE MY-24 was dissolved uniformly inthe mixture of the epoxy resins and hardener, but was not dissolved inthe acrylic rubber and was deposited as particles. After the completecuring of the adhesive, the epoxy resins and the acrylic rubber wereseparated into a disperse phase and a continuous phase, respectively.

Example 11

[0156] An adhesive film bearing a carrier film was produced in the samemanner as in Example 10, except that the curing accelerator was replacedby FUJICURE FXR-1030 produced by Fuji Kasei Co., Ltd. that is anamine-ureido adduct compound. In the adhesive of the B-stage state,FUJICURE FXR-1030 was dissolved uniformly in the mixture of the epoxyresins and hardener, but was not dissolved in the acrylic rubber and wasdeposited as particles.

Reference Example 2

[0157] An adhesive film bearing a carrier film was produced in the samemanner as in Example 1, except that the curing accelerator was replacedby 0.5 parts by weight of 1-cyanoethyl-2-phenylimidazole (trade name:CURESOLE 2PZ-CN produced by Shikoku Kasei Kogyo Co., Ltd.). In theadhesive of the B-stage state, CURESOLE 2PZ-CN was dissolved in both theepoxy resins and the acrylic rubber.

[0158] Usable periods were evaluated by sticking a semiconductor chip onan interconnecting substrate the base material of which was a 25μm-thick polyimide film with each of the obtained adhesive members afterthey had been stored at 25° C. for 1 to 6 months (sticking conditions:temperature: 160° C., pressure: 1.5 MPa, time: 3 seconds), and observingthe adhesives for filling ability in the interconnecting lines with anultrasonic microscope. The adhesives that left no vacant spaces betweenthem and the interconnecting lines on the interconnecting substrateswere rated as ◯, and those that left vacant spaces as X. The results aregiven in Table 2. TABLE 2 Result of Evaluation Reference Example 10Example 11 Example 2 Filling ability Initial stage ◯ ◯ ◯ 1 month ◯ ◯ ◯ 2months ◯ ◯ X 3 months ◯ ◯ X 4 months ◯ ◯ X 5 months X X X 6 months X X XUsable period 4 months 4 months 1 month

[0159] In Example 10 wherein an amine-epoxy adduct latent curingaccelerator was used, a good result of a long usable period wasobtained. In Example 11 wherein an amine-ureido adduct latent curingaccelerator was used, a good result of a long usable period wasobtained. The usable period was short in Reference Example 2 wherein thecuring accelerator used was an imidazole that has a low molecular weightand is soluble in both the rubber and the epoxy resins.

INDUSTRIAL APPLICABILITY

[0160] The adhesive A of the present invention is improved in thestorage stability of its B-stage film by the use of a latent curingaccelerator. The adhesives containing amine adducts, MY-24 and FXR-1030,excelled in heat resistance and moisture resistance. Particularly, atthe time of curing, adhesives containing the amine-epoxy adduct latentcuring accelerator could be cured fast enough to give completely curedproducts without foaming. Among the adhesive members of the presentinvention, those containing adduct, particularly amine adduct, moreparticularly amine-epoxy adduct latent curing accelerators particularlyexcel in heat resistance and moisture resistance. Because of sucheffects, the present invention can efficiently provide adhesive membersnecessary for semiconductor devices to exhibit high reliability.

[0161] The adhesive film made from the adhesive B of the presentinvention is significantly advantageous compared with conventionaladhesive films because it has a long usable period, can be stored for along period and is easy of production control. That is, the adhesive andthe adhesive film have excellent storage stability. By using theadhesive of claim 12 that, in a B-state state, forms a disperse phasecontaining an epoxy resin and a hardener as main components and acontinuous phase containing a high molecular weight component having aweight average molecular weight of 100,000 or more, an adhesive filmexcelling further in adhesion, heat resistance and film processabilitycan be produced. In particular, an adhesive containing as the highmolecular weight component resin forming the continuous phase anepoxidized acrylic copolymer having a glycidyl (meth)acrylate copolymerunit content of 2 to 6 wt. % is advantageous because it can form anadhesive film having higher adhesion and better heat resistance. The useof an amine-epoxy adduct compound as a curing accelerator can provide anadhesive that is further excellent in that it does not foam on curingand forms an adhesive film having low elasticity and good heatresistance and moisture resistance. Thus, the present invention canprovide adhesive films, interconnecting substrates for semiconductormounting and semiconductor devices, which exhibit particularly highstorage stability.

What is claimed is:
 1. An adhesive, comprising (1) 100 parts by weight of an epoxy resin and a hardener therefor, (2) 75 to 300 parts by weight of an epoxidized acrylic copolymer having a glycidyl (meth)acrylate unit content of 0.5 to 6 wt. %, a glass transition temperature Tg of −10° C. or higher and a weight average molecular weight of 100,000 or more and (3) 0.1 to 20 parts by weight of a latent curing accelerator.
 2. An adhesive, comprising (1) 100 parts by weight of an epoxy resin and a hardener therefor, (2) 5 to 40 parts by weight of a high molecular weight resin being compatible with the epoxy resin and having a weight average molecular weight of 30,000 or more, (3) 75 to 300 parts by weight of an epoxidized acrylic copolymer having a glycidyl (meth)acrylate unit content of 0.5 to 6 wt. %, a glass transition temperature Tg of −10° C. or higher and a weight average molecular weight of 100,000 or more and (4) 0.1 to 20 parts by weight of a latent curing accelerator.
 3. The adhesive of claim 2, wherein the latent curing accelerator is an adduct curing accelerator.
 4. The adhesive of claim 3, wherein the latent curing accelerator is an amine adduct.
 5. The adhesive of claim 4, wherein the latent curing accelerator is an amine-epoxy adduct.
 6. The adhesive of claim 2, which contains 1 to 20 parts by volume of an inorganic filler relative to 100 parts by volume of a resin content of the adhesive.
 7. The adhesive of claim 6, wherein the inorganic filler is alumina, silica, aluminum hydroxide or antimony oxide.
 8. The adhesive of claim 2, which has generated 10 to 40% of heat to be generated by complete curing thereof as measured by DSC.
 9. The adhesive of claim 2, which has a residual solvent content of 5 wt. % or less.
 10. The adhesive of claim 2, which gives a cured product thereof having a storage modulus of 20 to 2,000 MPa at 25° C. and having a storage modulus of 3 to 50 MPa at 260° C. as measured by using a dynamic viscoelasticity measuring apparatus.
 11. The adhesive of claim 1, wherein the latent curing accelerator is an adduct curing accelerator.
 12. The adhesive of claim 11, wherein the latent curing accelerator is an amine adduct.
 13. The adhesive of claim 12, wherein the latent curing accelerator is an amine-epoxy adduct.
 14. The adhesive of claim 1, which contains 1 to 20 parts by volume of an inorganic filler relative to 100 parts by volume of a resin content of the adhesive.
 15. The adhesive of claim 14, wherein the inorganic filler is alumina, silica, aluminum hydroxide or antimony oxide.
 16. The adhesive of claim 1, which has generated 10 to 40% of heat to be generated by complete curing thereof as measured by DSC.
 17. The adhesive of claim 1, which has a residual solvent content of 5 wt. % or less.
 18. The adhesive of claim 1, which gives a cured product thereof having a storage modulus of 20 to 2,000 MPa at 25° C. and having a storage modulus of 3 to 50 MPa at 260° C. as measured by using a dynamic viscoelasticity measuring apparatus.
 19. An adhesive member of a film form, comprising a carrier film and a layer of the adhesive of claim 1 formed on the carrier film.
 20. An adhesive member, comprising a core material and a layer of the adhesive of claim 1 formed on each side of the core material.
 21. The adhesive member of claim 20, wherein the core material is a heat resistant thermoplastic film.
 22. The adhesive member of claim 21, wherein the heat resistant thermoplastic film has a softening temperature of 260° C. or higher.
 23. The adhesive member of claim 21, wherein the heat resistant thermoplastic film is a porous film.
 24. The adhesive member of claim 21, wherein the heat resistant thermoplastic film is a liquid crystalline polymer.
 25. The adhesive member of claim 21, wherein the heat resistant thermoplastic film is a polyamideimide, a polyimide, a polyetherimide or a polyether sulfone.
 26. The adhesive member of claim 21, wherein the heat resistant thermoplastic film is a polytetrafluoroethylene, an ethylene-tetrafluoroethylene copolymer, a tetrafluoroethylene-hexafluoropropylene copolymer or a tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer.
 27. An interconnecting substrate for semiconductor mounting, comprising: an interconnecting substrate having a semiconductor chip mounting surface, and the adhesive member of claim 19, stuck on the semiconductor chip-mounting surface of the interconnecting substrate.
 28. A semiconductor device, comprising a semiconductor chip and an interconnecting substrate bonded together by using the adhesive member of claim
 19. 29. A semiconductor device, comprising an interconnecting substrate and a semiconductor chip having an area of 70% or more of an area of the interconnecting substrate, the interconnecting substrate and the semiconductor chip being bonded together by using the adhesive member of claim
 19. 30. An interconnecting substrate for semiconductor mounting, comprising: an interconnecting substrate having a semiconductor chip mounting surface, and the adhesive member of claim 20 stuck on the semiconductor chip mounting surface of the interconnecting substrate.
 31. A semiconductor device, comprising a semiconductor chip and an interconnecting substrate bonded together by the adhesive member of claim
 20. 32. A semiconductor device, comprising an interconnecting substrate and a semiconductor chip having an area of 70% or more of an area of the interconnecting substrate, the interconnecting substrate and the semiconductor chip being bonded together by the adhesive member of claim
 20. 33. An adhesive member of a film form, comprising a carrier film and a layer of the adhesive of claim 2 formed on the carrier film.
 34. An adhesive member, comprising a core material and a layer of the adhesive of claim 2 formed on each side of the core material.
 35. The adhesive member of claim 34, wherein the core material is a heat resistant thermoplastic film.
 36. The adhesive member of claim 35, wherein the heat resistant thermoplastic film has a softening temperature of 260° C. or higher.
 37. The adhesive member of claim 35, wherein the heat resistant thermoplastic film is a porous film.
 38. The adhesive member of claim 35, wherein the heat resistant thermoplastic film is a liquid crystalline polymer.
 39. The adhesive member of claim 35, wherein the heat resistant thermoplastic film is a polyamideimide, a polyimide, a polyetherimide or a polyether sulfone.
 40. The adhesive member of claim 35, wherein the heat resistant thermoplastic film is a polytetrafluoroethylene, an ethylene-tetrafluoroethylene copolymer, a tetrafluoroethylene-hexafluoropropylene copolymer or a tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer.
 41. An interconnecting substrate for semiconductor mounting, comprising: an interconnecting substrate having a semiconductor chip mounting surface, and the adhesive member of claim 33, stuck on the semiconductor chip-mounting surface of the interconnecting substrate.
 42. A semiconductor device, comprising a semiconductor chip and an interconnecting substrate bonded together by using the adhesive member of claim
 33. 43. A semiconductor device, comprising an interconnecting substrate and a semiconductor chip having an area of 70% or more of an area of the interconnecting substrate, the interconnecting substrate and the semiconductor chip being bonded together by using the adhesive member of claim
 33. 44. An interconnecting substrate for semiconductor mounting, comprising: an interconnecting substrate having a semiconductor chip mounting surface, and the adhesive member of claim 34 stuck on the semiconductor chip mounting surface of the interconnecting substrate.
 45. A semiconductor device, comprising a semiconductor chip and an interconnecting substrate bonded together by the adhesive member of claim
 34. 46. A semiconductor device, comprising an interconnecting substrate and a semiconductor chip having an area of 70% or more of an area of interconnecting substrate, the interconnecting substrate and the semiconductor chip being bonded together by the adhesive member of claim
 34. 